active_record: fix for MySQL on connection error

[mssola]

Signed-off-by: Miquel Sabaté Solà [email protected]

[mssola]

Basically, when upgrading my application to Rails 5, I had the issue being mentioned here. The workaround was to add an initializer that manually serialized the parameters.

That being said, in MySQL, this involves a connection attempt (for some reason this is not the case for PostgreSQL). This was all fine for me, but recently I had to run some tasks which specifically forbid having the database around (kind of a weird scenario, I know 😅). These tasks failed miserably on MySQL because the database was purposely turned off (again, same scenario on PostgreSQL support was fine).

This PR rescues this case (connection not being established), ignoring the failure and logging a warning (as it is done when the database was not found). I've tried to use higher-level exceptions (that is, from ActiveRecord and such), but it all seemed to fail on MySQL. The only thing that worked is to rescue this low-level error from the MySQL backend.

I don't know if there's a better solution for this. If so, I'll gladly update this PR in whatever direction it is decided.

[pokonski]

Hey @mssola, yeah this will do since we already catch related errors as you noticed in the code.

Thanks for this!

[mssola]

@pokonski thanks a lot for this 😄

One question though: because of this issue, we had to fork this gem and release a patch-level release that included this fix. Would it be possible from your side to release a patch-level release that includes this fix (as you did, for example, for the 1.6.2 release). This way I'll be able to get rid off this fork 😁

[pokonski]

@mssola Funny you should ask, this is now released as 1.6.3 💥 😁

[mssola]

Nice! Thanks 👏